Thesis (M.M.A.)--University of Washington, 2009. / Title from Web page (viewed on Feb. 3, 2010). Includes bibliographical references (leaves 41-45).

Thesis (M.M.A.)--University of Washington, 2009. / Includes bibliographical references (leaves 41-45). Also available on the World Wide Web.

Thesis (Ed.D.)--Texas Christian University, 2009. / Title from dissertation title page (viewed Apr. 19, 2010). Includes abstract. Includes bibliographical references.

Observations or a small group of pikas, (Ochotona princeps) occupying a southwest facing roadfill on Mt. Hood, Oregon (1518 m) were made during the fall or 1976. Territorial sizes of 305.5 m2 and 121 m2 were determined based on territorial displays. These territories were compared with those observed in other studies. The mean distance to the nearest neighbor was 15.1 m. A pair relationship between two of the pikas and a dominance order are discussed. The seasonal progression of the haypiles and the reactions of the pikas to other animals are also noted.

No description available.

The Hood River Valley, located 100 kilometers east of Portland, Oregon, is in the transition zone between two geologic provinces--the High Cascades and the Columbia Plateau. The entire valley is probably underlain by Columbia River Basalt, but it crops out only on steep hillsides and in stream valleys. The base of the basalt is not exposed in the thesis area. The basalt is overlain by Pliocene and Quaternary basalt and andesite, volcanic sediments and glacial debris. The stratigraphy of the Columbia River Basalt is useful in determining the path of the basalt flows into western Oregon, in mapping the structure and in reconstructing the tectonic development of the northern Oregon Cascades.

Ten mountain lakes were analyzed in order that they be assigned a trophic status. The lakes which are located in the Mount Hood National Forest of Oregon are Anvil, Beaver Pond, Cripple Creek, Fish, Gifford, Monon, Ollalie, Rimrock, Round, and Sportsman. The purpose of this report is to determine the productivity of these waters. Data were collected for analyses of temperature, dissolved oxygen concentration, Secchi depth, major ion concentration, light intensity versus depth, alkalinity, phytoplanktcn species composition/total density, and zooplankton species composition/total density. Samples were collected in Van Darn sampling bottles and returned to the laboratory for chemical analyses and taxonomic identification of biological organisms. Field profiles were taken for light intensity, temperature, dissolved oxygen concentration, specific conductivity, and depth using portable electronic equipment. A Secchi disk was used in the field for obtaining light extinction data. The lakes were assigned a trophic status according to carlson's Trophic State Index (Carlson, 1977). Beaver Pond Lake which is the most productive lake of the 10 surveyed had an average Secchi depth of 1.7 meters, an average soluble reactive phosphorous concentration of 59.8 ug/L, and an average chlorophyll-a concentration of 29.3 ug/L for the dates sampled. These values are consistent with lakes which are eutrophic. Ollalie Lake had an average Secchi depth of 13.2 meters, an average soluble reactive phosphorous concentration of 1.64 ug/L, and an average chlorophyll-a concentration of 0.28 ugfL. This lake is ultraoligotrophic-to-oligotrophic according to the Carlson index. The other lakes of the study were assigned values for trophic state which are somewhere between those assigned to Beaver Pond and Ollalie lakes. The 10 lakes studied for this report were compared to lakes studied for the compilation of the Western Lake survey (Landers, et. al. 1987). It was noted that Beaver Pond, Round, and Sportsman lakes are nutrient rich while Monon, Ollalie, and Gifford, are nutrient poor when compared to other lakes located in the Pacific Northwest. Anvil, Cripple Creek, Fish, and Rimrock lakes have profiles consistent with the majority of mountain lakes located in the area.

No description available.

Soils from two active earthflows, two earthflow deposits, and three non-earthflow landforms are examined to determine if a connection exists between near-surface soil properties and rates of earthflow movement. The study area is located in the Clackamas Ranger District of the Mt. Hood National Forest in the northern Oregon Cascades. Its geology consists of clay-bearing volcaniclastic formations overlain by unaltered flows of andesite and basalt, a combination that contributed to large-scale landsliding during the late Pleistocene. Deposits from these landslides now cover much of the valley floor, and it is from these deposits that earthflows tend to mobilize. The main hypothesis is that near-surface soil properties reflect earthflow movement and may be used to distinguish between active and inactive earthflows. The results support this hypothesis and indicate that soils in each of the three categories show clear differences in terms of their physical properties. The mean field moisture content of active earthflows is 56 percent, while that of earthflow deposits is 46 percent and that of non-earthflow landforms is 36 percent. All samples from active earthflows exhibit plasticity, whereas 90 percent of samples from earthflow deposits and only 25 percent of samples from nonearthflow landforms exhibit plasticity. The mean liquid limit of active earthflows is 78 percent, compared to 60 percent for earthflow deposits and 46 percent for non-earthflow landforms. The mean plasticity index of active earthflows is 41 percent, compared to only 13 percent for earthflow deposits and non-earthflow landforms. These differences are largely attributed to clay content and clay type. The mean clay content of active earthflows is 46 percent, compared to 24 percent for earthflow deposits and only 5 percent for nonearthflow landforms. In contrast, the mean sand content of active earthflows is 20 percent, while earthflow deposits contain 40 percent and non-earthflow landforms 50 percent. This difference in particle sizes is reflected in friction angle. Active earthflows have a mean friction angle of 15 degrees, compared to 24 degrees for earthflow deposits and 31 degrees for non-earthflow landforms. These results indicate that soil properties can be used to draw distinctions between active and inactive earthflows. However, soil properties are much less effective at distinguishing between active earthflows that move at different rates. For example, Junction earthflow, which moves only a few centimeters per year, is composed of soils that indicate it to be less stable than the Collowash earthflow, which moves approximately 2 meters per year. The reason for this discrepancy is that, in addition to soil properties, the rate of earthflow movement depends on the complimentary effects of hydrology, slope angle, toe erosion, and boundary roughness. Many ancient landslide deposits in the Mt. Hood National Forest are poised for action and may mobilize upon the slightest provocation. Since this is not seen as a "desired future condition" there is a need to differentiate between those deposits with a potential for reactivation and those likely to remain dormant. Examining the physical properties of soils appears to be one way to do this, and the information collected is valuable to land managers and earth scientists alike.

This research documents the Holocene glacial history of Mount Hood, Cascade Mountains, Oregon by analyzing a set of three lateral moraines abutting Eliot Glacier, the largest glacier on the mountain. This study seeks to: 1) establish the relative ages of these lateral moraines and 2) determine if these features represent distinct glacial advances. The hypothesis is that the lateral moraines for Eliot Glacier represent three distinct periods of glacial advance based on their position relative to the current glacier and other diagnostic indicators. Soil profiles of three positions (shoulder, backslope, and footslope) on the distal side of each lateral moraine were described in the field and samples were taken from each horizon for laboratory analyses of pH and particle size. The results of the soil analysis show that the soils developing on the moraine closest to the current glacier are poorly developed and significantly younger than the other two features. The closest moraine likely dates to the Little Ice Age (600-150 YBP) and has soils with an A/C profile and a classification of Andic Cryopsamment. The soils on the middle and furthest moraines from the glacier are similar in the profile sequence (Andic Haplocryepts). Silt bulges were noted in the mid-slope pits. The furthest moraine has deeper horizons and more color development than the middle moraine. Ash layers were found in the backslope soil profile (36-51cm deep) on the middle moraine. Additional lab testing confirms the ash layers originated from Mount Hood, but no date can be assigned. The eruptive history of Mount Hood points to the Timberline eruptive period (1,500 YBP) as a likely candidate for one of the ash deposits. This evidence suggests the middle moraine was actively forming during this period and is intermediate in age between the furthest moraine and the Little Ice Age Moraine; hence, this sequence of moraines indicates three distinct periods of glacial advance in the Neoglacial.